I am not sure but with theories and the trailer, i think korra is going to go through a huge change with the recovery. Not only that, but i believe korra is going to have both mental and physical challenges when recovering from the incident in the book 3 finale.
Like aang, i believe that korra grows a fear for the avatar state, seeing her self like that in such a vulnerable yet strong way frightens her. And she has to deal with those fears. i believe one contribution to dealing those fears is her adventure in the swamp. She will start to hallucinate and start to face challenges. I believe that she'll also have mental breakdowns and reactions to hallucinating about her self in the avatar state. I am not sure here but what do you think guys? this is my theory of her character developement in book 4.